The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Internal combustion engines combust an air/fuel mixture within cylinders to generate drive torque. The air may be drawn into an inlet of a compressor (of a turbocharger) and through an air inlet system that may be regulated by a throttle. The air may be filtered by an air filter located upstream from (i.e., before) the compressor. The filtered air may then be distributed to a plurality of cylinders and combined with fuel to create the A/F mixture. The air may be combined with fuel prior to entering the cylinders (i.e., port fuel injection) or the air may be combined with the fuel within the cylinders (i.e., direct fuel injection). The A/F mixture may then be compressed by pistons and ignited. The ignition of the A/F mixture may be via a spark generated by a spark plug (i.e., spark ignition) and/or the ignition of the A/F mixture may be “automatic” due to increased temperature and/or pressure of the A/F mixture (i.e., compression ignition).
The ignition of the A/F mixture drives the pistons, which rotatably turn a crankshaft generating drive torque. The drive torque may be transferred to a driveline (e.g., wheels) of a vehicle via a transmission that includes a plurality of gear ratios. Exhaust gas resulting from combustion may be expelled from the cylinders through an exhaust manifold and an exhaust treatment system. The exhaust gas may also be recirculated into the intake manifold via an exhaust gas recirculation (EGR) system and/or recirculated to power a turbocharger that further pressurizes the air drawn into the intake manifold.